The third-generation Jaguar XJ, the X350, was introduced in 2003 succeeding the X308. The new XJ saw the return of the six-cylinder engine - the 3.0-litre V6, the same one featured in the S-Type and the X-Type. The V6 petrol was later discontinued upon the introduction of the 2.7-litre V6 diesel in 2005. The X350 also featured V8 engines offered in larger 3.5 and 4.2 litre sizes as well as a supercharged 4.2 Litre and a 6-speed automatic gearbox.

 The X350 has an all-aluminium body making it 40 per cent lighter and 60 per cent stiffer than its predecessor resulting in better fuel economy, a dynamic perfomance and enhanced safety and durability. The interior features new levels of spaciousness with electrically adjustable steering column and front seats. The X350 was the most technologically advanced Jaguar of its time featuring an array of cutting edge electronic technology enabling it to compete favourably with its German rivals.

An optional touch screen interface controls default settings, satellite navigation, the Alpine audio system, and bluetooth telephone. JaguarVoice - voice-activated control of systems including audio controls, telephone, climate control and navigation - is available as standard. Also standard on all models is the self-levelling air-suspension which improves the car's ride and handling. An electronic park brake offers the convenience of drive-away release when you shift gear from parking and automatically applies the handbrake when the ignition key is removed.

 Driver assistance features include Adaptive Cruise Control, Traction control and Dynamic Stability Control. The DSC system has been further improved to correct understeer and oversteer. The X350 was facelifted as the X358 for the 2008 model year with minor changes including revised rear lights and door mirrors with integrated side repeaters. The last X350 vehicle was produced in March 2009 making way for the Jaguar XJ X351.